/*
  太原学院计算机技术系(C)版权所有。
 * 
 */
package cn.edu.tyu.fiance.thingstype.servlet;

import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import cn.edu.tyu.finance.util.DbUtil;
import cn.edu.tyu.finance.util.StringUtil;

/**
 * Servlet implementation class LoginServlet
用户登录
 */
@WebServlet("/LoginServlet")
public class LoginServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public LoginServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	       处理网页发来的get请求 另一个是post
	 * @param request 请求对象
	 * @param response 响应对象
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
         //1.接收用户名和密码
		String uname=request.getParameter("username");
		String upsw=request.getParameter("userpsw");
		String upswMD5=StringUtil.getMD5(upsw);//相同的数加密后的值总是一样的
		//2.连接数据库，查询
		Connection conn=null;
		PreparedStatement pstmt =null;
		ResultSet rs=null; //结果集
		conn= DbUtil.getConnection();
		String sql =" SELECT * FROM users WHERE username=? AND userpsw=?";
		try {
			pstmt=conn.prepareStatement(sql);
			pstmt.setString(1,uname);
			pstmt.setString(2,upswMD5);
			rs=pstmt.executeQuery();
			if(rs.next()) //查询到了
			{
				response.sendRedirect("ok.jsp");
			}
			else 
			{
				response.sendRedirect("fail.jsp");
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally 
		{
			DbUtil.backConn(conn, pstmt, rs);
		}
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	     处理网页发来的post请求 另一个是get
	 * @param request 请求对象
	 * @param response 响应对象
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}